Two academics who wrote a paper suggesting that it should logically be permissible to kill babies at birth who would have fitted the criteria for abortion during pregnancy have been subjected to death threats, according to the journal editor.

The pair – Alberto Giubilini from the University of Milan and Monash University in Melbourne and Francesca Minerva from the University of Melbourne and Oxford University, argued in the journal that, as "potential persons", newborn babies, like foetuses, do not have the same moral status as "actual persons".

What they preferred to call "after-birth abortion" rather than infanticide should be allowed not only for babies with abnormalities, such as Down's syndrome, which had not been detected during the pregnancy, but also newborns whose parents would have been granted an abortion because they felt they could not psychologically or materially cope with a child.

The newborn baby is a non-person, argue the ethicists, because they have no sense of their own existence. At a few days old, they say, newborns are "potential persons" but not actual persons, in the same way that a foetus is a potential person. So the interests of their parents over-ride theirs.

The paper has "elicited personally abusive correspondence to the authors, threatening their lives and personal safety", writes Savulescu in a blog for his journal.

"The journal has received a string of abusive emails for its decision to publish this article. This abuse is typically anonymous."

Many of the comments come from an anti-abortion website in the US called The Blaze. Savulescu, who notes that the comments include openly racist remarks, cites some of the emails:

"I would personally kill anyone doing a after-birth abortion if I had the chance," says one.

"These two devils in human skin need to be delivered for immediate execution under their code of 'after-birth abortions' they want to commit murder – that is all it is! MURDER!!!" writes another critic.

Savulescu argues that the journal exists not to promote one moral view over another but to present reasoned argument. The controversial paper builds on arguments that have been presented by other philosophers in the past, he says.

"The authors provocatively argue that there is no moral difference between a foetus and a newborn. Their capacities are relevantly similar. If abortion is permissible, infanticide should be permissible. The authors proceed logically from premises which many people accept to a conclusion that many of those people would reject," he said.

He accepts that the argument, in fact, plays into the hands of the anti-abortion lobby. "Many people will argue that on this basis abortion should be recriminalised. Those arguments can be well made and the journal would publish a paper that made such a case coherently, originally and with application to issues of public or medical concern," he writes.

He sees the online attacks as attempts to stifle free speech. "What is disturbing is not the arguments in this paper nor its publication in an ethics journal. It is the hostile, abusive, threatening responses that it has elicited. More than ever, proper academic discussion and freedom are under threat from fanatics opposed to the very values of a liberal society," he said.